  #include <QApplication>
 #include <QFont>
 #include <QPushButton>
 #include <QWidget>

 int main(int argc, char *argv[])
 {
     QApplication app(argc, argv);

     QWidget window;
     window.resize(200, 110);

     QPushButton quit("Quit", &window);
     quit.setFont(QFont("Times", 18, QFont::Bold));
     quit.setGeometry(10, 40, 180, 40);
     QObject::connect(&quit, SIGNAL(clicked()), &app, SLOT(quit()));

     window.show();
     return app.exec();
 }